Pathological gambling is an increasing problem in the United States, with significant financial, psychological and public health consequences. Controlled trials examining the efficacy of therapeutic interventions for pathological gamblers, however, are sparse. Gamblers Anonymous (GA) is the most popular form of treatment, and some evidence suggests that cognitive-behavioral (CB) treatment may be useful. In addition, minimal treatment using a self-help manual has been shown effective. To assess the most efficacious and cost-effective treatment strategy, 220 individuals meeting DSM-IV criteria for pathological gambling will be randomly assigned to one of three interventions: (1) assessment, referral to GA, and 8-weeks of professionally- delivered CB therapy; (2) assessment, referral to GA, and an 8- week CB self-help manual; or, (3) a control/comparison treatment consisting of assessment and referral to GA alone. Subjects will be recruited from advertisements and among applicants to the Compulsive Gambling Treatment Program at the State of Connecticut Department of Mental Health and Addiction Services. Gambling and related problems will be assessed using standardized instruments pre-treatment, at month 1, at month 2 (post-treatment), and at 6- and 12-month follow up evaluations. The project will address the following questions: Are brief, CB treatments more effective than GA referral alone in reducing gambling during the treatment period and for significant periods following treatment? How does a CB self-help manual compare to professionally-delivered CB treatment? Are the effects of the interventions reflected in better psychosocial functioning during treatment and throughout the follow-up period? What are the societal costs associated with pathological gambling, and how do the interventions differ in their cost-effectiveness in terms of reducing these costs? Are certain patient characteristics associated with better outcomes in some of the treatment conditions? Are the treatments effective in diverse populations that include women and minority gamblers?